Formatting, spinlock, and 32-bit iOS frameworks

[mackworth]

Turns out iOS has the same issue as macOS, if you are generating 32-bit versions (i.e. supporting prior to 11.0). armv7 and arm64 need to be lipo'd together (as do the simulator versions). Otherwise, you get a similar error message when trying to build the framework.

In addition, this PR includes:

• The SpinLock fix for iOS thread race fix from issue $50
• Formatting changes I discussed in issue #57
• Some minor log message changes, reflecting concerns/issues I had the first time I used script
• and just for the heck of it, updating to boost 1.75.0 as default

I included an update to the changelog (embarrassingly called "changeling" in commit msg) that reflect these changes and last PR.

If you want me to separate these commits or make any other changes, happy to do so.

[mackworth]

After I did this pull request, I saw there was one outstanding from @paynerc. His implementation was better, so I've ditched mine and merged his into the other changes I made.

[mackworth]

And after some more testing, realized that the exact same issue applies to Mac Catalyst: if you have both architectures, they need to be lipo'd together before putting into XCFramework.

[faithfracture]

@mackworth Sorry - been focusing on other things recently. Regarding your previous comment, does that mean there needs to be a change to this PR, or is it still ready to go?

[mackworth]

Yes, I've made those changes. I believe we're good to go, although I'd love @paynerc to review.

[mackworth]

just a bump to see if @paynerc approves and if @faithfracture should proceed.